Family of five-speed transmission mechanisms having a stationary interconnecting member

ABSTRACT

The family of transmissions has a plurality of members that can be utilized in powertrains to provide at least five forward speed ratios and one reverse speed ratio. The transmission family members include three planetary gear sets, first and second interconnecting members, and four clutches. The powertrain includes an engine and torque converter that is continuously connected to at least one member of the third planetary gear set and an output member that is continuously connected with another member of the third planetary gear set. The second interconnecting member continuously connects members of the first and second planetary gear sets with the transmission housing. The four clutches provide interconnections between various gear members, the first interconnecting member, and with the input and the output shaft, and are operated in combinations of two to establish at least five forward speed ratios.

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to a family of power transmissionshaving three planetary gear sets with a stationary interconnectingmember, wherein the planetary gear sets are controlled by four clutchesto provide at least five forward speed ratios and one reverse speedratio.

[0003] 2. Background Art

[0004] Passenger vehicles include a powertrain that is comprised of anengine, multi-speed transmission, and a differential or final drive. Themulti-speed transmission increases the overall operating range of thevehicle by permitting the engine to operate through its torque range anumber of times. The number of forward speed ratios that are availablein the transmission determines the number of times the engine torquerange is repeated. Early automatic transmissions had two speed ranges.This severely limited the overall speed range of the vehicle andtherefore required a relatively large engine that could produce a widespeed and torque range. This resulted in the engine operating at aspecific fuel consumption point during cruising, other than the mostefficient point. Therefore, manually-shifted (countershafttransmissions) were the most popular.

[0005] With the advent of three- and four-speed automatic transmissions,the automatic shifting (planetary gear) transmission increased inpopularity with the motoring public. These transmissions improved theoperating performance and fuel economy of the vehicle. The increasednumber of speed ratios reduces the step size between ratios andtherefore improves the shift quality of the transmission by making theratio interchanges substantially imperceptible to the operator undernormal vehicle acceleration.

[0006] It has been suggested that the number of forward speed ratios beincreased to five and even six speeds. Five-speed transmissions aredisclosed in U.S. Pat. Nos. 5,879,264; 5,984,825; 5,997,429; 6,007,450;and 6,056,665 issued to Raghavan, Hebbale and Usoro on Mar. 9, 1999;Nov. 16, 1999; Dec. 7, 1999; Dec. 28, 1999 and May 2, 2000,respectively; and U.S. Pat. No. 5,951,432 issued to Wehking, Hebbale,Raghavan and Usoro on Sep. 14, 1999. Six-speed transmissions aredisclosed in U.S. Pat. No. 4,070,927 issued to Polak on Jan. 31, 1978;U.S. Pat. No. 6,071,208 issued to Koivunen on Jun. 6, 2000; U.S. Pat.No. 5,106,352 issued to Lepelletier on Apr. 21, 1992; and U.S. Pat. No.5,599,251 issued to Beim and McCarrick on Feb. 4, 1997.

[0007] Five-speed transmissions offer several advantages over four-speedtransmissions, including improved vehicle acceleration and improved fueleconomy. While many trucks employ power transmissions, such as Polak,having six or more forward gear ratios, passenger cars are stillmanufactured with three- and four-speed automatic transmissions andrelatively few five or six-speed devices due to the size and complexityof these transmissions. The Raghavan, Hebbale, Usoro and Wehking patentsemploy two planetary gear sets, and five or six torque transmittingmechanisms to provide five forward speeds.

SUMMARY OF THE INVENTION

[0008] It is an object of the present invention to provide an improvedfamily of transmissions having three planetary gear sets controlled toprovide at least five forward speed ratios.

[0009] In one aspect of the present invention, the family oftransmissions has three planetary gear sets, each of which includes afirst, second and third member, which members may comprise a sun gear, aring gear, or a planet carrier assembly member.

[0010] In another aspect of the present invention, each of the planetarygear sets may be of the single pinion-type or of the double pinion-type.

[0011] In yet another aspect of the present invention, a firstinterconnecting member continuously interconnects the first member ofthe first planetary gear set with the first member of the secondplanetary gear set.

[0012] In still another aspect of the invention, a secondinterconnecting member continuously interconnects the second member ofthe first planetary gear set and the second member of the secondplanetary gear set with the transmission housing.

[0013] In yet a further aspect of the invention, each family memberincorporates an input shaft which is continuously interconnected with amember of the third planetary gear set, and an output shaft which iscontinuously connected with another member of the third planetary gearset.

[0014] In another aspect of the invention, a first clutch selectivelyinterconnects the third member of the first planetary gear set with theinput shaft, the output shaft, or a member of the third planetary gearset.

[0015] In still a further aspect of the invention, a second clutchselectively interconnects the third member of the second planetary gearset with the input shaft, the output shaft, or a member of the thirdplanetary gear set.

[0016] In a still further aspect of the invention, a third clutchselectively interconnects the first interconnecting member with theinput shaft, the output shaft, or a member of the third planetary gearset.

[0017] In a still further aspect of the invention, a fourth clutchselectively interconnects the third member of the first or secondplanetary gear set or the first interconnecting member with the inputshaft, the output shaft, or a member of the third planetary gear set.

[0018] In still another aspect of the invention, the four clutches areselectively engageable in combinations of two to yield at least fiveforward speed ratios and one reverse speed ratio.

[0019] The above objects and other objects, features, and advantages ofthe present invention are readily apparent from the following detaileddescription of the best modes for carrying out the invention when takenin connection with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[0020]FIG. 1a is a schematic representation of a powertrain including aplanetary transmission incorporating a family member of the presentinvention;

[0021]FIG. 1b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 1a;

[0022]FIG. 2a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0023]FIG. 2b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 2a;

[0024]FIG. 3a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0025]FIG. 3b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 3a;

[0026]FIG. 4a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0027]FIG. 4b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 4a;

[0028]FIG. 5a is a schematic representation of a power-train having aplanetary transmission incorporating another family member of thepresent invention;

[0029]FIG. 5b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 4a;

[0030]FIG. 6a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0031]FIG. 6b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 6a;

[0032]FIG. 7a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0033]FIG. 7b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 7a;

[0034]FIG. 8a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0035]FIG. 8b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 8a;

[0036]FIG. 9a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0037]FIG. 9b is a truth table and chart depicting some of the operatingcharacteristics of the powertrain shown in FIG. 9a;

[0038]FIG. 10a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention;

[0039]FIG. 10b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 10a;

[0040]FIG. 11a is a schematic representation of a powertrain having aplanetary transmission incorporating another family member of thepresent invention; and

[0041]FIG. 11b is a truth table and chart depicting some of theoperating characteristics of the powertrain shown in FIG. 11a.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0042] Referring to the drawings, wherein like characters represent thesame or corresponding parts throughout the several views, there is shownin FIG. 1a a powertrain 10 having a conventional engine and torqueconverter 12, a planetary transmission 14, and a conventional finaldrive mechanism 16.

[0043] The planetary transmission 14 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 18, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 18 includes three planetary gear sets 20, 30 and 40.

[0044] The planetary gear set 20 includes a sun gear member 22, a ringgear member 24, and a planet carrier assembly 26. The planet carrierassembly 26 includes a plurality of pinion gears 27 rotatably mounted ona carrier member 29 and disposed in meshing relationship with both thesun gear member 22 and the ring gear member 24.

[0045] The planetary gear set 30 includes a sun gear member 32, a ringgear member 34, and a planet carrier assembly member 36. The planetcarrier assembly member 36 includes a plurality of pinion gears 37rotatably mounted on a carrier member 39 and disposed in meshingrelationship with both the sun gear member 32 and the ring gear member34.

[0046] The planetary gear set 40 includes a sun gear member 42, a ringgear member 44, and a planet carrier assembly member 46. The planetcarrier assembly member 46 includes a plurality of pinion gears 47rotatably mounted on a carrier member 49 and disposed in meshingrelationship with both the sun gear member 42 and the ring gear member44.

[0047] The planetary gear arrangement 18 also includes four torquetransmitting mechanisms 50, 52, 54 and 56. The torque-transmittingmechanisms 50, 52, 54 and 56 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0048] The input shaft 17 is continuously connected with the ring gearmember 44, and the output shaft 19 is continuously connected with theplanet carrier assembly member 46. The sun gear member 22 iscontinuously connected with the sun gear member 32 through theinterconnecting member 70. The planet carrier assembly members 26 and 36are continuously connected with the transmission housing 60 through theinterconnecting member 72.

[0049] The sun gear member 32 is selectively connectable with the sungear member 42 through the clutch 50. The ring gear member 24 isselectively connectable with the ring gear member 44 through the clutch52. The ring gear member 34 is selectively connectable with the sun gearmember 42 through the clutch 54. The ring gear member 34 is selectivelyconnectable with the planet carrier assembly member 46 through theclutch 56.

[0050] As shown in FIG. 1b, and in particular the truth table disclosedtherein, the torque-transmitting mechanisms are selectively engaged incombinations of two to provide five forward speed ratios and a reversespeed ratio. It should also be noted in the truth table that thetorque-transmitting mechanism 50 remains engaged through a neutralcondition, thereby simplifying the forward/reverse interchange.

[0051] To establish the reverse speed ratio, the clutches 50 and 52 areengaged. The clutch 50 connects the sun gear member 32 to the sun gearmember 42, and the clutch 52 connects the ring gear member 24 to thering gear member 44. The planet carrier assembly members 26 and 36 donot rotate. The ring gear members 24 and 44 rotate at the same speed asthe input shaft. The sun gear members 22, 32 and 42 rotate at the samespeed. The sun gear member 22 rotates at a speed determined from thespeed of the ring gear member 24 and the ring gear/sun gear tooth ratioof the planetary gear set 20. The planet carrier assembly member 46, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the ring gear member 44, the speed of the sun gear member 42,and the ring gear/sun gear tooth ratio of the planetary gear set 40. Theoverall numerical value of the reverse speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets20 and 40.

[0052] To establish the first forward speed ratio, the clutches 50 and56 are engaged. The clutch 50 connects the sun gear member 32 to the sungear member 42, and the clutch 56 connects the ring gear member 34 tothe planet carrier assembly member 46. The planet carrier assemblymembers 26 and 36 do not rotate. The sun gear members 22, 32 and 42rotate at the same speed. The ring gear member 34 rotates at the samespeed as the planet carrier assembly member 46 and the output shaft 19.The ring gear member 34 rotates at a speed determined from the speed ofthe sun gear member 32 and the ring gear/sun gear tooth ratio of theplanetary gear set 30. The ring gear member 44 rotates at the same speedas the input shaft 17. The planet carrier assembly member 46, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the ring gear member 44, the speed of the sun gear member 42,and the ring gear/sun gear tooth ratio of the planetary gear set 40. Theoverall numerical value of the first forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets30 and 40.

[0053] The second forward speed ratio is established with the engagementof the clutches 50 and 54. The clutch 50 connects the sun gear member 32to the sun gear member 42, and the clutch 54 connects the ring gearmember 34 to the sun gear member 42. The planet carrier assembly members26 and 36 do not rotate. The sun gear members 22, 32 and 42 rotate atthe same speed as the ring gear member 34. The ring gear member 44rotates at the same speed as the input shaft 17. The planet carrierassembly member 46 rotates at the same speed as the output shaft 19. Theplanet carrier assembly member 46 rotates at a speed determined from thespeed of the ring gear member 44, the speed of the sun gear member 42,and the ring gear/sun gear tooth ratio of the planetary gear set 40. Thenumerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set40.

[0054] The third forward speed ratio is established with the engagementof the clutches 54 and 56. In this configuration, the input shaft 17 isdirectly connected to the output shaft 19. The numerical value of thethird forward speed ratio is 1.

[0055] The fourth forward speed ratio is established with the engagementof the clutches 52 and 54. The clutch 52 connects the ring gear member24 to the ring gear member 44, and the clutch 54 connects the ring gearmember 34 to the sun gear member 42. The planet carrier assembly members26 and 36 do not rotate. The ring gear members 24 and 44 rotate at thesame speed as the input shaft 17. The sun gear members 22 and 32 rotateat the same speed. The sun gear member 22 rotates at a speed determinedfrom the speed of the ring gear member 24 and the ring gear/sun geartooth ratio of the planetary gear set 20. The ring gear member 34rotates at the same speed as the sun gear member 42. The ring gearmember 34 rotates at a speed determined from the speed of the sun gearmember 32 and the ring gear/sun gear tooth ratio of the planetary gearset 30. The planet carrier assembly member 46, and therefore the outputshaft 19, rotates at a speed determined from the speed of the ring gearmember 44, the speed of the sun gear member 42, and the ring gear/sungear tooth ratio of the planetary gear set 40. The numerical value ofthe fourth forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 20, 30 and 40.

[0056] The fifth forward speed ratio is established with the engagementof the clutches 52 and 56. The clutch 52 connects the ring gear member24 to the ring gear member 44, and the clutch 56 connects the ring gearmember 34 to the planet carrier assembly member 46. The planet carrierassembly members 26 and 36 do not rotate. The ring gear members 24 and44 rotate at the same speed as the input shaft 17. The sun gear members22 and 32 rotate at the same speed. The sun gear member 22 rotates at aspeed determined from the speed of the ring gear member 24 and the ringgear/sun gear tooth ratio of the planetary gear set 20. The ring gearmember 34 rotates at the same speed as the planet carrier assemblymember 46 and the output shaft 19. The ring gear member 34 rotates at aspeed determined from the speed of the sun gear member 32 and the ringgear/sun gear tooth ratio of the planetary gear set 30. The numericalvalue of the fifth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 20 and 30.

[0057] As set forth above, the engagement schedules for thetorque-transmitting mechanisms are shown in the truth table of FIG. 1b.This truth table also provides an example of speed ratios that areavailable utilizing the ring gear/sun gear tooth ratios given by way ofexample in FIG. 1b. The R1/S1 value is the tooth ratio of the planetarygear set 20; the R2/S2 value is the tooth ratio of the planetary gearset 30; and the R3/S3 value is the tooth ratio of the planetary gear set40. Also, the chart of FIG. 1b describes the ratio steps that areattained utilizing the sample of tooth ratios given. For example, thestep ratio between the first and second forward ratios is 1.61, whilethe step ratio between the reverse and first forward ratio is −0.68. Itcan also be readily determined from the truth table of FIG. 1b that allof the single step forward ratio interchanges are of the singletransition variety, as are the double step forward ratio interchanges.

[0058]FIG. 2a shows a powertrain 110 having a conventional engine andtorque converter 12, a planetary transmission 114, and a conventionalfinal drive mechanism 16.

[0059] The planetary transmission 114 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 118, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 118 includes three planetary gear sets 120, 130 and 140.

[0060] The planetary gear set 120 includes a sun gear member 122, a ringgear member 124, and a planet carrier assembly 126. The planet carrierassembly 126 includes a plurality of pinion gears 127 rotatably mountedon a carrier member 129 and disposed in meshing relationship with boththe sun gear member 122 and the ring gear member 124.

[0061] The planetary gear set 130 includes a sun gear member 132, a ringgear member 134, and a planet carrier assembly member 136. The planetcarrier assembly member 136 includes a plurality of pinion gears 137rotatably mounted on a carrier member 139 and disposed in meshingrelationship with both the sun gear member 132 and the ring gear member134.

[0062] The planetary gear set 140 includes a sun gear member 142, a ringgear member 144, and a planet carrier assembly member 146. The planetcarrier assembly member 146 includes a plurality of pinion gears 147rotatably mounted on a carrier member 149 and disposed in meshingrelationship with both the sun gear member 142 and the ring gear member144.

[0063] The planetary gear arrangement 118 also includes four torquetransmitting mechanisms 150, 152, 154 and 156. The torque-transmittingmechanisms 150, 152, 154 and 156 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0064] The input shaft 17 is continuously connected with the sun gearmember 142, and the output shaft 19 is continuously connected with theplanet carrier assembly member 146. The ring gear member 124 iscontinuously connected with the ring gear member 134 through theinterconnecting member 170. The sun gear member 132 and planet carrierassembly member 126 are continuously connected with the transmissionhousing 160 through the interconnecting member 172.

[0065] The ring gear member 134 is selectively connectable with the ringgear member 144 through the clutch 150. The ring gear member 134 isselectively connectable with the planet carrier assembly member 146through the clutch 152. The sun gear member 122 is selectivelyconnectable with the sun gear member 142 through the clutch 154. Theplanet carrier assembly member 136 is selectively connectable with thering gear member 144 through the clutch 156.

[0066] The truth table of FIG. 2b describes the engagement sequenceutilized to provide five forward speed ratios and a reverse speed ratioin the planetary gear arrangement 118 shown in FIG. 2a.

[0067] To establish the reverse speed ratio, the clutches 152 and 154are engaged. The clutch 152 connects the ring gear member 134 to theplanet carrier assembly member 146, and the clutch 154 connects the sungear member 122 to the sun gear member 142. The planet carrier assemblymember 126 and sun gear member 132 do not rotate. The ring gear members124 and 134 rotate at the same speed as the planet carrier assemblymember 146 and the output shaft 19. The sun gear members 122 and 142rotate at the same speed as the input shaft 17. The ring gear member 124rotates at a speed determined from the speed of the sun gear member 122and the ring gear/sun gear tooth ratio of the planetary gear set 120.The numerical value of the reverse speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 120.

[0068] The first forward speed ratio is established with the engagementof the clutches 150 and 154. The clutch 150 connects the ring gearmember 134 to the ring gear member 144, and the clutch 154 connects thesun gear member 122 to the sun gear member 142. The planet carrierassembly member 126 and sun gear member 132 do not rotate. The ring gearmembers 124, 134 and 144 rotate at the same speed. The sun gear members122 and 142 rotate at the same speed as the input shaft 17. The ringgear member 124 rotates at a speed determined from the speed of the sungear member 122 and the ring gear/sun gear tooth ratio of the planetarygear set 120. The planet carrier assembly member 146, and therefore theoutput shaft 19, rotates at a speed determined from the speed of thering gear member 144, the speed of the sun gear member 142, and the ringgear/sun gear tooth ratio of the planetary gear set 140. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 120 and 140.

[0069] The second forward speed ratio is established with the engagementof the clutches 154 and 156. The clutch 154 connects the sun gear member122 to the sun gear member 142, and the clutch 156 connects the planetcarrier assembly member 136 to the ring gear member 144. The planetcarrier assembly member 126 and sun gear member 132 do not rotate. Thering gear members 124 and 134 rotate at the same speed. The sun gearmembers 122 and 142 rotate at the same speed as the input shaft 17. Thering gear member 124 rotates at a speed determined from the speed of thesun gear member 122 and the ring gear/sun gear tooth ratio of theplanetary gear set 120. The planet carrier assembly member 136 rotatesat the same speed as the ring gear member 144. The planet carrierassembly member 136 rotates at a speed determined from the speed of thering gear member 134 and the ring gear/sun gear tooth ratio of theplanetary gear set 130. The planet carrier assembly member 146, andtherefore the output shaft 19, rotates at a speed determined from thespeed of the ring gear member 144, the speed of the sun gear member 142,and the ring gear/sun gear tooth ratio of the planetary gear set 140.The numerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets120, 130 and 140.

[0070] The third forward speed ratio is established with the engagementof the clutches 150 and 156. The clutch 150 connects the ring gearmember 134 to the ring gear member 144, and the clutch 156 connects theplanet carrier assembly member 136 to the ring gear member 144. Theplanet carrier assembly member 126 and sun gear member 132 do notrotate. The ring gear members 124, 134 and 144 all rotate at the samespeed as the planet carrier assembly member 136. The sun gear member 142rotates at the same speed as the input shaft 17. The planet carrierassembly member 146, and therefore the output shaft 19, rotates at aspeed determined from the speed of the ring gear member 144, the speedof the sun gear member 142, and the ring gear/sun gear tooth ratio ofthe planetary gear set 140. The numerical value of the third forwardspeed ratio is determined utilizing the ring gear/sun gear tooth ratioof the planetary gear set 140.

[0071] The fourth forward speed ratio is established with the engagementof the clutches 152 and 156. The clutch 152 connects the ring gearmember 134 to the planet carrier assembly member 146, and the clutch 156connects the planet carrier assembly member 136 to the ring gear member144. The planet carrier assembly member 126 and sun gear member 132 donot rotate. The ring gear members 124 and 134 rotate at the same speedas the planet carrier assembly member 146 and the output shaft 19. Theplanet carrier assembly member 136 rotates at the same speed as the ringgear member 144. The planet carrier assembly member 136 rotates at aspeed determined from the speed of the ring gear member 134 and the ringgear/sun gear tooth ratio of the planetary gear set 130. The sun gearmember 142 rotates at the same speed as the input shaft 17. The planetcarrier assembly member 146 rotates at a speed determined from the speedof the ring gear member 144, the speed of the sun gear member 142, andthe ring gear/sun gear tooth ratio of the planetary gear set 140. Thenumerical value of the fourth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets130 and 140.

[0072] The fifth forward speed ratio is established with the engagementof the clutches 150 and 152. In this configuration, the input shaft 17is directly connected to the output shaft 19. The numerical value of thefifth forward speed ratio is 1.

[0073] As set forth above, the truth table of FIG. 2b describes theengagement sequence of the torque transmitting mechanisms utilized toprovide a reverse drive ratio and five forward speed ratios. It can bereadily determined from the truth table that all the single step forwardinterchanges are of the single transition type, as are the double stepforward interchanges. The truth table also provides an example of theratios that can be attained with the family members shown in FIG. 2autilizing the sample tooth ratios given in FIG. 2b. The R1/S1 value isthe tooth ratio of the planetary gear set 120; the R2/S2 value is thetooth ratio of the planetary gear set 130; and the R3/S3 value is thetooth ratio of the planetary gear set 140. Also shown in FIG. 2b are theratio steps between single step ratios in the forward direction as wellas the reverse to first ratio step. For example, the first to secondstep ratio is 1.43.

[0074] Turning to FIG. 3a, a powertrain 210 includes the engine andtorque converter 12, a planetary transmission 214, and a final drivemechanism 16. The planetary transmission 214 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 218, and an output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 218 includes three planetary gear sets 220, 230 and 240.

[0075] The planetary gear set 220 includes a sun gear member 222, a ringgear member 224, and a planet carrier assembly 226. The planet carrierassembly 226 includes a plurality of pinion gears 227 rotatably mountedon a carrier member 229 and disposed in meshing relationship with boththe sun gear member 222 and the ring gear member 224.

[0076] The planetary gear set 230 includes a sun gear member 232, a ringgear member 234, and a planet carrier assembly member 236. The planetcarrier assembly member 236 includes a plurality of pinion gears 237rotatably mounted on a carrier member 239 and disposed in meshingrelationship with both the sun gear member 232 and the ring gear member234.

[0077] The planetary gear set 240 includes a sun gear member 242, a ringgear member 244, and a planet carrier assembly member 246. The planetcarrier assembly member 246 includes a plurality of pinion gears 247rotatably mounted on a carrier member 249 and disposed in meshingrelationship with both the sun gear member 242 and the ring gear member244.

[0078] The planetary gear arrangement 218 also includes four torquetransmitting mechanisms 250, 252, 254 and 256. The torque-transmittingmechanisms 250, 252, 254 and 256 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0079] The input shaft 17 is continuously connected with the sun gearmember 242, and the output shaft 19 is continuously connected with thering gear member 244. The ring gear member 224 is continuously connectedwith the planet carrier assembly member 236 through the interconnectingmember 270. The sun gear members 222 and 232 are continuously connectedwith the transmission housing 260 through the interconnecting member272.

[0080] The planet carrier assembly member 236 is selectively connectablewith the planet carrier assembly member 246 through the clutch 150. Theplanet carrier assembly member 236 is selectively connectable with thesun gear member 242 through the clutch 252. The planet carrier assemblymember 226 is selectively connectable with the ring gear member 244through the clutch 254. The ring gear member 234 is selectivelyconnectable with the planet carrier assembly member 246 through theclutch 256.

[0081] As shown in the truth table in FIG. 3b, the torque transmittingmechanisms are engaged in combinations of two to establish five forwardspeed ratios and one reverse ratio. It should be also noted that thetorque transmitting mechanism 256 can remain engaged through the neutralcondition, thereby simplifying the forward/reverse interchange.

[0082] The reverse speed ratio is established with the engagement of theclutches 250 and 256. The clutch 250 connects the planet carrierassembly member 236 to the planet carrier assembly member 246, and theclutch 256 connects the ring gear member 234 to the planet carrierassembly member 246. The ring gear members 224 and 234 and planetcarrier assembly members 236 and 246 rotate at the same speed. The sungear members 222 and 232 do not rotate. The sun gear member 242 rotatesat the same speed as the input shaft 17. The ring gear member 244rotates at the same speed as the output shaft 19. The ring gear member244 rotates at a speed determined from the speed of the sun gear member242, the speed of the planet carrier assembly member 246, and the ringgear/sun gear tooth ratio of the planetary gear set 240. The numericalvalue of the reverse speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 240.

[0083] The first forward speed ratio is established with the engagementof the clutches 254 and 256. The clutch 254 connects the planet carrierassembly member 226 to the ring gear member 244. The clutch 256 connectsthe ring gear member 234 to the planet carrier assembly member 246. Thesun gear members 222 and 232 do not rotate. The ring gear member 224rotates at the same speed as the planet carrier assembly member 236. Theplanet carrier assembly member 226 rotates at the same speed as the ringgear member 244 and the output shaft 19. The planet carrier assemblymember 226 rotates at a speed determined from the speed of the ring gearmember 224 and the ring gear/sun gear tooth ratio of the planetary gearset 220. The ring gear member 234 rotates at the same speed as theplanet carrier assembly member 246. The planet carrier assembly member236 rotates at a speed determined from the speed of the ring gear member234 and the ring gear/sun gear tooth ratio of the planetary gear set230. The sun gear member 242 rotates at the same speed as the inputshaft 17. The ring gear member 244, and therefore the output shaft 19,rotates at a speed determined from the speed of the sun gear member 242,the speed of the planet carrier assembly member 246, and the ringgear/sun gear tooth ratio of the planetary gear set 240. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 220, 230 and 240.

[0084] The second forward speed ratio is established with the engagementof the clutches 250 and 254. The clutch 250 connects the planet carrierassembly member 236 to the planet carrier assembly member 246, and theclutch 254 connects the planet carrier assembly member 226 to the ringgear member 244. The sun gear members 222 and 232 do not rotate. Theplanet carrier assembly member 226 rotates at the same speed as the ringgear member 244 and the output shaft 19. The ring gear member 224rotates at the same speed as the planet carrier assembly members 236 and246. The planet carrier assembly member 226 rotates at a speeddetermined from the speed of the ring gear member 224 and the ringgear/sun gear tooth ratio of the planetary gear set 220. The sun gearmember 242 rotates at the same speed as the input shaft 17. The ringgear member 244, and therefore the output shaft 19, rotates at a speeddetermined from the speed of the sun gear member 242, the speed of theplanet carrier assembly member 246, and the ring gear/sun gear toothratio of the planetary gear set 240. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 220 and 240.

[0085] The third forward speed ratio is established with the engagementof the clutches 252 and 254. The clutch 252 connects the planet carrierassembly member 236 to the sun gear member 242, and the clutch 254connects the planet carrier assembly member 226 to the ring gear member244. The sun gear members 222 and 232 do not rotate. The ring gearmember 224 rotates at the same speed as the planet carrier assemblymember 236, the sun gear member 242, and the input shaft 17. The planetcarrier assembly member 226 rotates at the same speed as the ring gearmember 244 and the output shaft 19. The planet carrier assembly member226 rotates at a speed determined from the speed of the ring gear member224 and the ring gear/sun gear tooth ratio of the planetary gear set220. The numerical value of the third forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set220.

[0086] The fourth forward speed ratio is established with the engagementof the clutches 250 and 252. In this configuration, the input shaft 17is directly connected to the output shaft 19. The numerical value of thefourth forward speed ratio is 1.

[0087] The fifth forward speed ratio is established with the engagementof the clutches 252 and 256. The clutch 252 connects the planet carrierassembly member 236 to the sun gear member 242, and the clutch 256connects the ring gear member 234 to the planet carrier assembly member246. The sun gear members 222 and 232 do not rotate. The ring gearmember 224 rotates at the same speed as the planet carrier assemblymember 236, the sun gear member 242, and the input shaft 17. The ringgear member 234 rotates at the same speed as the planet carrier assemblymember 246. The ring gear member 234 rotates at a speed determined fromthe speed of the planet carrier assembly member 236 and the ringgear/sun gear tooth ratio of the planetary gear set 230. The ring gearmember 244 rotates at the same speed as the output shaft 19. The ringgear member 244 rotates at a speed determined from the speed of the sungear member 242, the speed of the planet carrier assembly member 246,and the ring gear/sun gear tooth ratio of the planetary gear set 240.The numerical value of the fifth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets230 and 240.

[0088] As previously set forth, the truth table of FIG. 3b describes thecombinations of engagements utilized for the five forward speed ratiosand reverse ratio. The truth table also provides an example of speedratios that are available with the family member described above. Theseexamples of speed ratios are determined utilizing the tooth ratios givenin FIG. 3b. The R1/S1 value is the tooth ratio of the planetary gear set220; the R2/S2 value is the tooth ratio of the planetary gear set 230;and the R3/S3 value is the tooth ratio of the planetary gear set 240.Also depicted in FIG. 3b is a chart representing the ratio steps betweenadjacent forward speed ratios and the reverse to first forward speedratio. For example, the first to second ratio interchange has a step of1.63. It can also be readily determined from the truth table of FIG. 3bthat all of the single step forward ratio interchanges are of the singletransition variety, as are all of the double step forward interchanges.

[0089] A powertrain 310, shown in FIG. 4a, includes the engine andtorque converter 12, a planetary transmission 314, and the final drivemechanism 16. The planetary transmission 314 includes an input shaft 17continuously connected with the engine and torque converter 12, aplanetary gear arrangement 318, and output shaft 19 continuouslyconnected with the final drive mechanism 16. The planetary geararrangement 318 includes three planetary gear sets 320, 330 and 340.

[0090] The planetary gear set 320 includes a sun gear member 322, a ringgear member 324, and a planet carrier assembly member 326. The planetcarrier assembly member 326 includes a plurality of pinion gears 327rotatably mounted on a carrier member 329 and disposed in meshingrelationship with both the sun gear member 322 and the ring gear member324.

[0091] The planetary gear set 330 includes a sun gear member 332, a ringgear member 334, and a planet carrier assembly member 336. The planetcarrier assembly member 336 includes a plurality of pinion gears 337rotatably mounted on a carrier member 339 and disposed in meshingrelationship with both the sun gear member 332 and the ring gear member334.

[0092] The planetary gear set 340 includes a sun gear member 342, a ringgear member 344, and a planet carrier assembly member 346. The planetcarrier assembly member 346 includes a plurality of pinion gears 347rotatably mounted on a carrier member 349 and disposed in meshingrelationship with both the sun gear member 342 and the ring gear member344.

[0093] The planetary gear arrangement 318 also includes four torquetransmitting mechanisms 350, 352, 354 and 356. The torque-transmittingmechanisms 350, 352, 354 and 356 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0094] The input shaft 17 is continuously connected with the planetcarrier assembly member 346, and the output shaft 19 is continuouslyconnected with the ring gear member 344. The planet carrier assemblymember 326 is continuously connected with the sun gear member 332through the interconnecting member 370. The ring gear members 324 and334 are continuously connected with the transmission housing 360 throughthe interconnecting member 372.

[0095] The sun gear member 332 is selectively connectable with theplanet carrier assembly member 346 through the clutch 350. The sun gearmember 332 is selectively connectable with the sun gear member 342through the clutch 352. The sun gear member 322 is selectivelyconnectable with the sun gear member 342 through the clutch 354. Theplanet carrier assembly member 336 is selectively connectable with thering gear member 344 through the clutch 356.

[0096] The truth tables given in FIGS. 4b, 5 b, 6 b, 7 b, 8 b, 9 b, 10 band 11 b show the engagement sequences for the torque transmittingmechanisms to provide at least five forward speed ratios and one reverseratio. As shown and described for the configurations in FIGS. 1a, 2 aand 3 a, those skilled in the art will understand from the respectivetruth tables how the speed ratios are established through the planetarygear sets identified in the written description.

[0097] The truth table shown in FIG. 4b describes the engagementcombination and the engagement sequence necessary to provide the reversedrive ratio and the five forward speed ratios. A sample of the numericalvalues for the ratios is also provided in the truth table of FIG. 4b.These values are determined utilizing the ring gear/sun gear toothratios also given in FIG. 4b. The R1/S1 value is the tooth ratio for theplanetary gear set 320; the R2/S2 value is the tooth ratio for theplanetary gear set 330; and the R3/S3 value is the tooth ratio for theplanetary gear set 340. Also given in FIG. 4b is a chart describing thestep ratios between the adjacent forward speed ratios and the reverse tofirst forward speed ratio. For example, the first to second forwardspeed ratio step is 1.4. It can be readily determined from the truthtable of FIG. 4b that each of the forward single step ratio interchangesis a single transition shift, as are the double step interchanges. Thechart also shows that the torque transmitting mechanism 354 can beengaged through the neutral condition to simplify the forward/reverseinterchange.

[0098] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 320 and 340. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 320, 330 and 340.The numerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set330. The numerical value of the third forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets330 and 340. The numerical value of the fourth forward speed ratio is 1.The numerical value of the fifth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratio of the planetary gear set340.

[0099] A powertrain 410, shown in FIG. 5a, includes the engine andtorque converter 12, a planetary transmission 414 and the final drivemechanism 16. The planetary transmission 414 includes a planetary geararrangement 418, input shaft 17 and output shaft 19. The planetary geararrangement 418 includes three simple planetary gear sets 420, 430 and440.

[0100] The planetary gear set 420 includes a sun gear member 422, a ringgear member 424, and a planet carrier assembly 426. The planet carrierassembly 426 includes a plurality of pinion gears 427 rotatably mountedon a carrier member 429 and disposed in meshing relationship with boththe sun gear member 422 and the ring gear member 424.

[0101] The planetary gear set 430 includes a sun gear member 432, a ringgear member 434, and a planet carrier assembly member 436. The planetcarrier assembly member 436 includes a plurality of pinion gears 437rotatably mounted on a carrier member 439 and disposed in meshingrelationship with both the sun gear member 432 and the ring gear member434.

[0102] The planetary gear set 440 includes a sun gear member 442, a ringgear member 444, and a planet carrier assembly member 446. The planetcarrier assembly member 446 includes a plurality of pinion gears 447rotatably mounted on a carrier member 449 and disposed in meshingrelationship with both the sun gear member 442 and the ring gear member444.

[0103] The planetary gear arrangement 418 also includes four torquetransmitting mechanisms 450, 452, 454 and 456. The torque transmittingmechanisms 450, 452, 454 and 458 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0104] The input shaft 17 is continuously connected with the sun gearmember 442, and the output shaft 19 is continuously connected with thering gear member 444. The planet carrier assembly member 426 iscontinuously connected with the ring gear member 434 through theinterconnecting member 470. The sun gear members 422 and 432 arecontinuously connected with the transmission housing 460 through theinterconnecting member 472.

[0105] The ring gear member 434 is selectively connectable with theplanet carrier assembly member 446 through the clutch 450. The ring gearmember 424 is selectively connectable with the planet carrier assemblymember 446 through the clutch 452. The ring gear member 424 isselectively connectable with the sun gear member 442 through the clutch454. The planet carrier assembly member 436 is selectively connectablewith the ring gear member 444 through the clutch 456.

[0106] The truth table shown in FIG. 5b describes the engagementcombination and sequence of the torque transmitting mechanisms 450, 452,454 and 456 that are employed to provide the reverse drive ratio and thefive forward speed ratios. It should be noted that the torquetransmitting mechanism 452 is engaged through the neutral condition tosimplify the forward/reverse interchange.

[0107] Also given in the truth table of FIG. 5b is a set of numericalvalues that are attainable with the present invention utilizing the ringgear/sun gear tooth ratios shown. The R1/S1 value is the tooth ratio ofthe planetary gear set 420; the R2/S2 value is the tooth ratio of theplanetary gear set 430; and the R3/S3 value is the tooth ratio of theplanetary gear set 440. As can also be determined from the truth tableof FIG. 5b, the single step forward interchanges are single transitionshifts, as are the double step interchanges in the forward direction.

[0108]FIG. 5b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward speed ratio.For example, the ratio step between the first and second forward speedratios is 1.63.

[0109] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 440. The numerical value ofthe first forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 420, 430 and 440. Thenumerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets430 and 440. The numerical value of the third forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 420 and 430. The numerical value of the fourthforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 420 and 440. The numerical value ofthe fifth forward speed ratio is 1.

[0110] A powertrain 510, shown in FIG. 6a, includes an engine and torqueconverter 12, a planetary gear transmission 514 and the final drivemechanism 16. The planetary transmission 514 includes the input shaft17, a planetary gear arrangement 518 and the output shaft 19. Theplanetary gear arrangement 518 includes three planetary gear sets 520,530 and 540.

[0111] The planetary gear set 520 includes a sun gear member 522, a ringgear member 524, and a planet carrier assembly 526. The planet carrierassembly 526 includes a plurality of pinion gears 527 rotatably mountedon a carrier member 529 and disposed in meshing relationship with boththe sun gear member 522 and the ring gear member 524.

[0112] The planetary gear set 530 includes a sun gear member 532, a ringgear member 534, and a planet carrier assembly member 536. The planetcarrier assembly member 536 includes a plurality of pinion gears 537rotatably mounted on a carrier member 539 and disposed in meshingrelationship with both the sun gear member 532 and the ring gear member534.

[0113] The planetary gear set 540 includes a sun gear member 542, a ringgear member 544, and a planet carrier assembly member 546. The planetcarrier assembly member 546 includes a plurality of pinion gears 547rotatably mounted on a carrier member 549 and disposed in meshingrelationship with both the sun gear member 542 and the ring gear member544.

[0114] The planetary gear arrangement 518 also includes four torquetransmitting mechanisms 550, 552, 554 and 556. The torque-transmittingmechanisms 550, 552, 554 and 556 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0115] The input shaft 17 is continuously connected with the ring gearmember 544, and the output shaft 19 is continuously connected with theplanet carrier assembly member 546. The ring gear member 524 iscontinuously connected with the planet carrier assembly member 536through the interconnecting member 570. The planet carrier assemblymember 526 and sun gear member 532 are continuously connected with thetransmission housing 560 through the interconnecting member 572.

[0116] The planet carrier assembly member 536 is selectively connectablewith the sun gear member 542 through the clutch 550. The planet carrierassembly member 536 is selectively connectable with the planet carrierassembly member 546 through the clutch 552. The sun gear member 522 isselectively connectable with the ring gear member 544 through the clutch554. The ring gear member 534 is selectively connectable with the sungear member 542 through the clutch 556.

[0117] The truth table shown in FIG. 6b describes the engagementsequence and combination of the torque transmitting mechanisms toprovide the reverse speed ratio and five forward speed ratios. It shouldbe noted that the torque transmitting mechanism 554 can remain engagedthrough the neutral condition, thereby simplifying the forward/reverseinterchange. It can also be determined from the truth table of FIG. 6bthat all of the single step forward ratio interchanges are of the singletransition variety, as are all of the double step forward interchanges.The chart of FIG. 6b describes the ratio steps between adjacent forwardspeed ratios and the ratio step between the reverse and first forwardspeed ratio.

[0118] Those skilled in the art, upon reviewing the truth table and theschematic representation of FIG. 6a, can determine that the numericalvalue of the reverse speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 520. The numericalvalue of the first forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 520, 530 and 540.The numerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets520 and 540. The numerical value of the third forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 540. The numerical value of the fourth forward speed ratiois 1. The numerical value of the fifth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets530 and 540.

[0119] The sample speed ratios given in the truth table are determinedutilizing the tooth ratio values also given in FIG. 6b. The R1/S1 valueis the tooth ratio of the planetary gear set 520; the R2/S2 value is thetooth ratio of the planetary gear set 530; and the R3/S3 value is thetooth ratio of the planetary gear set 540.

[0120] A powertrain 610, shown in FIG. 7a, has the engine and torqueconverter 12, a planetary transmission 614 and the final drive mechanism16. The planetary transmission 614 includes the input shaft 17, aplanetary gear arrangement 618 and the output shaft 19. The planetarygear arrangement 618 includes three planetary gear sets 620, 630 and640.

[0121] The planetary gear set 620 includes a sun gear member 622, a ringgear member 624, and a planet carrier assembly 626. The planet carrierassembly 626 includes a plurality of pinion gears 627 rotatably mountedon a carrier member 629 and disposed in meshing relationship with boththe sun gear member 622 and the ring gear member 624.

[0122] The planetary gear set 630 includes a sun gear member 632, a ringgear member 634, and a planet carrier assembly member 636. The planetcarrier assembly member 636 includes a plurality of pinion gears 637rotatably mounted on a carrier member 639 and disposed in meshingrelationship with both the sun gear member 632 and the ring gear member634.

[0123] The planetary gear set 640 includes a sun gear member 642, a ringgear member 644, and a planet carrier assembly member 646. The planetcarrier assembly member 646 includes a plurality of pinion gears 647rotatably mounted on a carrier member 649 and disposed in meshingrelationship with both the sun gear member 642 and the ring gear member644.

[0124] The planetary gear arrangement 618 also includes four torquetransmitting mechanisms 650, 652, 654 and 656. The torque-transmittingmechanisms 650, 652, 654 and 656 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0125] The input shaft 17 is continuously connected with the sun gearmember 642, and the output shaft 19 is continuously connected with theplanet carrier assembly member 646. The ring gear member 624 iscontinuously connected with the planet carrier assembly member 636through the interconnecting member 670. The planet carrier assemblymember 626 and sun gear member 632 are continuously connected with thetransmission housing 660 through the interconnecting member 672.

[0126] The ring gear member 624 is selectively connectable with the ringgear member 644 through the clutch 650. The sun gear member 622 isselectively connectable with the ring gear member 644 through the clutch652. The ring gear member 634 is selectively connectable with the sungear member 642 through the clutch 654. The ring gear member 634 isselectively connectable with the planet carrier assembly member 646through the clutch 656.

[0127] The truth table shown in FIG. 7b describes the combination oftorque transmitting mechanism engagements that will provide the reversedrive ratio and the five forward speed ratios, as well as the sequenceof these engagements and interchanges. The torque transmitting mechanism652 can be engaged through the neutral condition, thereby simplifyingthe forward/reverse interchange. It can be noted from the truth tablethat each of the single step forward interchanges are single transitionratio changes, and the double step forward interchanges are also singletransition ratio changes.

[0128] The ratio values given are by way of example and are establishedutilizing the ring gear/sun gear tooth ratios given in FIG. 7b. Forexample, the R1/S1 value is the tooth ratio of the planetary gear set620; the R2/S2 value is the tooth ratio of the planetary gear set 630;and the R3/S3 value is the tooth ratio of the planetary gear set 640.The ratio steps between adjacent forward ratios and the reverse to firstforward speed ratio are also given in FIG. 7b.

[0129] Those skilled in the art will, upon reviewing the truth table ofFIG. 7b, recognize that the numerical values of the reverse and firstforward speed ratios are determined utilizing the ring gear/sun geartooth ratios of the planetary gear sets 620, 630 and 640. The numericalvalue of the second forward speed ratio is determined utilizing the ringgear/sun gear tooth ratio of the planetary gear set 640. The numericalvalues of the third and fourth forward speed ratios are determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets630 and 640. The numerical value of the fifth forward speed ratio is 1.

[0130] A powertrain 710, shown in FIG. 8a, has the conventional engineand torque converter 12, a planetary transmission 714, and theconventional final drive mechanism 16. The engine and torque converter12 are drivingly connected with the planetary transmission 714 throughthe input shaft 17. The planetary transmission 714 is drivinglyconnected with the final drive mechanism 16 through the output shaft 19.The planetary transmission 714 includes a planetary gear arrangement 718that has a first planetary gear set 720, a second planetary gear set730, and a third planetary gear set 740.

[0131] The planetary gear set 720 includes a sun gear member 722, a ringgear member 724, and a planet carrier assembly 726. The planet carrierassembly 726 includes a plurality of pinion gears 727 rotatably mountedon a carrier member 729 and disposed in meshing relationship with boththe sun gear member 722 and the ring gear member 724.

[0132] The planetary gear set 730 includes a sun gear member 732, a ringgear member 734, and a planet carrier assembly member 736. The planetcarrier assembly member 736 includes a plurality of pinion gears 737rotatably mounted on a carrier member 739 and disposed in meshingrelationship with both the sun gear member 732 and the ring gear member734.

[0133] The planetary gear set 740 includes a sun gear member 742, a ringgear member 744, and a planet carrier assembly member 746. The planetcarrier assembly member 746 includes a plurality of pinion gears 747rotatably mounted on a carrier member 749 and disposed in meshingrelationship with both the sun gear member 742 and the ring gear member744.

[0134] The planetary gear arrangement 718 also includes four torquetransmitting mechanisms 750, 752, 754 and 756. The torque transmittingmechanisms 750, 752, 754 and 756 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0135] The input shaft 17 is continuously connected with the ring gearmember 744, and the output shaft 19 is continuously connected with theplanet carrier assembly member 746. The planet carrier assembly member726 is continuously connected with the sun gear member 732 through theinterconnecting member 770. The ring gear member 724 and planet carrierassembly member 736 are continuously connected with the transmissionhousing 760 through the interconnecting member 772.

[0136] The sun gear member 732 is selectively connectable with the sungear member 742 through the clutch 750. The planet carrier assemblymember 726 is selectively connectable with the ring gear member 744through the clutch 752. The sun gear member 722 is selectivelyconnectable with the sun gear member 742 through the clutch 754. Thering gear member 734 is selectively connectable with the planet carrierassembly member 746 through the clutch 756.

[0137] The truth table of FIG. 8b defines the torque transmittingmechanism engagement sequence utilized for each of the forward speedratios and the reverse speed ratio. Also given in the truth table is aset of numerical values that are attainable with the present inventionutilizing the ring gear/sun gear tooth ratios given in FIG. 8b. TheR1/S1 value is the tooth ratio of the planetary gear set 720; the R2/S2value is the tooth ratio of the planetary gear set 730; and the R3/S3value is the tooth ratio of the planetary gear set 740. As can also bedetermined from the truth table of FIG. 8b, the single step forwardinterchanges are single transition shifts, as are the double stepinterchanges in the forward direction.

[0138]FIG. 8b also provides a chart of the ratio steps between adjacentforward ratios and between the reverse and first forward ratio. Forexample, the ratio step between the first and second forward ratios is1.76. Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 730. The numerical value ofthe first forward speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 720, 730 and 740. Thenumerical value of the second forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets730 and 740. The numerical value of the third forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 740. The numerical value of the fourth forward speed ratiois 1. The numerical value of the fifth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets720 and 740.

[0139] A powertrain 810, shown in FIG. 9a, has the conventional engineand torque converter 12, a planetary transmission 814, and the finaldrive mechanism 16. The engine and torque converter 12 are drivinglyconnected with the planetary transmission 814 through the input shaft17. The planetary transmission 814 is drivingly connected with the finaldrive mechanism 16 through the output shaft 19. The planetarytransmission 814 includes a planetary gear arrangement 818 that has afirst planetary gear set 820, a second planetary gear set 830, and athird planetary gear set 840.

[0140] The planetary gear set 820 includes a sun gear member 822, a ringgear member 824, and a planet carrier assembly 826. The planet carrierassembly 826 includes a plurality of pinion gears 827 rotatably mountedon a carrier member 829 and disposed in meshing relationship with boththe sun gear member 822 and the ring gear member 824.

[0141] The planetary gear set 830 includes a sun gear member 832, a ringgear member 834, and a planet carrier assembly member 836. The planetcarrier assembly member 836 includes a plurality of pinion gears 837rotatably mounted on a carrier member 839 and disposed in meshingrelationship with both the sun gear member 832 and the ring gear member834.

[0142] The planetary gear set 840 includes a sun gear member 842, a ringgear member 844, and a planet carrier assembly member 846. The planetcarrier assembly member 846 includes a plurality of pinion gears 847rotatably mounted on a carrier member 849 and disposed in meshingrelationship with both the sun gear member 842 and the ring gear member844.

[0143] The planetary gear arrangement 818 also includes four torquetransmitting mechanisms 850, 852, 854 and 856. The torque-transmittingmechanisms 850, 852, 854 and 856 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0144] The input shaft 17 is continuously connected with the ring gearmember 844, and the output shaft 19 is continuously connected with theplanet carrier assembly member 846. The sun gear member 822 iscontinuously connected with the planet carrier assembly member 836through the interconnecting member 870. The ring gear member 834 andplanet carrier assembly member 826 are continuously connected with thetransmission housing 860 through the interconnecting member 872.

[0145] The planet carrier assembly member 836 is selectively connectablewith the ring gear member 844 through the clutch 850. The planet carrierassembly member 836 is selectively connectable with the sun gear member842 through the clutch 852. The ring gear member 824 is selectivelyconnectable with the planet carrier assembly member 846 through theclutch 854. The sun gear member 832 is selectively connectable with thesun gear member 842 through the clutch 856.

[0146] The truth table shown in FIG. 9b defines the torque transmittingmechanism engagement sequence that provides the reverse ratio and fiveforward speed ratios shown in the truth table and available with theplanetary gear arrangement 818. The truth table indicates that thetorque transmitting mechanism 854 can remain engaged through the neutralcondition, thereby simplifying the forward/reverse interchange. A sampleof numerical values for the individual ratios is also given in the truthtable of FIG. 9b. These numerical values have been calculated utilizingthe ring gear/sun gear tooth ratios also given by way of example in FIG.9b. The R1/S1 value is the tooth ratio of the planetary gear set 820;the R2/S2 value is the tooth ratio of the planetary gear set 830; andthe R3/S3 value is the tooth ratio of the planetary gear set 840. It canbe readily recognized from the truth table that all of the single anddouble step forward interchanges are single transition ratiointerchanges. FIG. 9b also describes the ratio steps between adjacentforward ratios and between the reverse and first forward speed ratio.For example, the ratio step between the first and second forward ratiosis 1.67.

[0147] Those skilled in the art of planetary transmissions willrecognize that the numerical value of the reverse speed ratio isdetermined utilizing the ring gear/sun gear tooth ratio of the planetarygear set 820. The numerical value of the first forward speed ratio isdetermined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 820, 830 and 840. The numerical value of the secondforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 820 and 840. The numerical value ofthe third forward speed ratio is determined utilizing the ring gear/sungear tooth ratio of the planetary gear set 840. The numerical value ofthe fourth forward speed ratio is 1. The numerical value of the fifthforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 830 and 840.

[0148] The powertrain 910, shown in FIG. 10a, includes the conventionalengine and torque converter 12, a planetary transmission 914, and theconventional final drive mechanism 16. The engine and torque converter12 are drivingly connected with the planetary transmission 914 throughthe input shaft 17. The planetary transmission 914 is drivinglyconnected with the final drive mechanism 16 through the output shaft 19.The planetary transmission 914 includes a planetary gear arrangement 918that has a first planetary gear set 920, a second planetary gear set930, and a third planetary gear set 940.

[0149] The planetary gear set 920 includes a sun gear member 922, a ringgear member 924, and a planet carrier assembly 926. The planet carrierassembly 926 includes a plurality of intermeshing pinion gears 927 thatare rotatably mounted on a carrier member 929 and disposed in meshingrelationship with the sun gear member 922 and the ring gear member 924,respectively.

[0150] The planetary gear set 930 includes a sun gear member 932, a ringgear member 934, and a planet carrier assembly member 936. The planetcarrier assembly member 936 includes a plurality of pinion gears 937rotatably mounted on a carrier member 939 and disposed in meshingrelationship with both the sun gear member 932 and the ring gear member934.

[0151] The planetary gear set 940 includes a sun gear member 942, a ringgear member 944, and a planet carrier assembly member 946. The planetcarrier assembly member 946 includes a plurality of pinion gears 947rotatably mounted on a carrier member 949 and disposed in meshingrelationship with both the sun gear member 942 and the ring gear member944.

[0152] The planetary gear arrangement 918 also includes four torquetransmitting mechanisms 950, 952, 954 and 956. The torque transmittingmechanisms 950, 952, 954 and 956 are rotating type torque transmittingmechanisms, commonly termed clutches.

[0153] The input shaft 17 is continuously connected with the planetcarrier assembly member 946, and the output shaft 19 is continuouslyconnected with the ring gear member 944. The sun gear member 922 iscontinuously connected with the sun gear member 932 through theinterconnecting member 970. The planet carrier assembly member 926 andring gear member 934 are continuously connected with the transmissionhousing 960 through the interconnecting member 972.

[0154] The sun gear member 932 is selectively connectable with the sungear member 942 through the clutch 950. The ring gear member 924 isselectively connectable with the planet carrier assembly member 946through the clutch 952. The planet carrier assembly member 936 isselectively connectable with the sun gear member 942 through the clutch954. The planet carrier assembly member 936 is selectively connectablewith the ring gear member 944 through the clutch 956.

[0155] The truth table of FIG. 10b describes the torque transmittingmechanism engagement sequence utilized to provide the reverse speedratio and five forward speed ratios. The truth table also provides a setof examples for the ratios for each of the reverse and forward speedratios. These numerical values have been determined utilizing the ringgear/sun gear tooth ratios given in FIG. 10b. The R1/S1 value is thetooth ratio of the planetary gear set 920; the R2/S2 value is the toothratio of the planetary gear set 930; and the R3/S3 value is the toothratio of the planetary gear set 940. It can also be determined from thetruth table of FIG. 10b that each of the forward single step and doublestep ratio interchanges are of the single transition variety.

[0156] Those skilled in the art, upon reviewing the engagementcombinations, will recognize that the numerical value of the reversespeed ratio is determined utilizing the ring gear/sun gear tooth ratiosof the planetary gear sets 920 and 930. The numerical value of the firstforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 930 and 940. The numerical value ofthe second forward speed ratio is 1. The numerical value of the thirdforward speed ratio is determined utilizing the ring gear/sun gear toothratio of the planetary gear set 940. The numerical value of the fourthforward speed ratio is determined utilizing the ring gear/sun gear toothratios of the planetary gear sets 920, 930 and 940. The numerical valueof the fifth forward speed ratio is determined utilizing the ringgear/sun gear tooth ratios of the planetary gear sets 920 and 940.

[0157] A powertrain 1010, shown in FIG. 11a, includes the conventionalengine and torque converter 12, a planetary transmission 1014, and theconventional final drive mechanism 16. The engine and torque converterare drivingly connected with the planetary transmission 1014 through theinput shaft 17. The planetary transmission 1014 is drivingly connectedwith the final drive mechanism 16 through the output shaft 19. Theplanetary transmission 1014 includes a planetary gear arrangement 1018that has a first planetary gear set 1020, a second planetary gear set1030, and a third planetary gear set 1040.

[0158] The planetary gear set 1020 includes a sun gear member 1022, aring gear member 1024, and a planet carrier assembly 1026. The planetcarrier assembly 1026 includes a plurality of pinion gears 1027rotatably mounted on a carrier member 1029 and disposed in meshingrelationship with both the sun gear member 1022 and the ring gear member1024.

[0159] The planetary gear set 1030 includes a sun gear member 1032, aring gear member 1034, and a planet carrier assembly member 1036. Theplanet carrier assembly member 1036 includes a plurality of pinion gears1037 rotatably mounted on a carrier member 1039 and disposed in meshingrelationship with both the sun gear member 1032 and the ring gear member1034.

[0160] The planetary gear set 1040 includes a sun gear member 1042, aring gear member 1044, and a planet carrier assembly member 1046. Theplanet carrier assembly member 1046 includes a plurality of pinion gears1047 and 1048 rotatably mounted on a carrier member 1049 and disposed inmeshing relationship with both the sun gear member 1042 and the ringgear member 1044.

[0161] The planetary gear arrangement 1018 also includes four torquetransmitting mechanisms 1050, 1052, 1054 and 1056. Thetorque-transmitting mechanisms 1050, 1052, 1054 and 1056 are rotatingtype torque transmitting mechanisms, commonly termed clutches.

[0162] The input shaft 17 is continuously connected with the ring gearmember 1044, and the output shaft 19 is continuously connected with theplanet carrier assembly member 1046. The sun gear member 1022 iscontinuously connected with the sun gear member 1032 through theinterconnecting member 1070. The planet carrier assembly member 1036 andring gear member 1024 are continuously connected with the transmissionhousing 1060 through the interconnecting member 1072.

[0163] The sun gear member 1032 is selectively connectable with the sungear member 1042 through the clutch 1050. The planet carrier assemblymember 1026 is selectively connectable with the sun gear member 1042through the clutch 1052. The planet carrier assembly member 1026 isselectively connectable with the planet carrier assembly member 1046through the clutch 1054. The ring gear member 1044 is selectivelyconnectable with the ring gear member 1034 through the clutch 1056.

[0164] The truth table shown in FIG. 11b describes the engagementcombinations and the engagement sequence necessary to provide thereverse drive ratio and the five forward speed ratios. A sample of thenumerical values for the ratios is also provided in the truth table ofFIG. 11b. These values are determined utilizing the ring gear/sun geartooth ratios also given in FIG. 11b. The R1/S1 value is the tooth ratiofor the planetary gear set 1020; the R2/S2 value is the tooth ratio forthe planetary gear set 1030; and the R3/S3 value is the tooth ratio forthe planetary gear set 1040. Also given in FIG. 11b is a chartdescribing the step ratios between the adjacent forward speed ratios andthe reverse to first forward speed ratio.

[0165] Those skilled in the art will recognize that the numerical valueof the reverse speed ratio is determined utilizing the ring gear/sungear tooth ratios of the planetary gear sets 1020 and 1030. Thenumerical value of the first forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratios of the planetary gear sets 1020 and1040. The numerical value of the second forward speed ratio is 1. Thenumerical value of the third forward speed ratio is determined utilizingthe ring gear/sun gear tooth ratio of the planetary gear set 1040. Thenumerical value of the fourth forward speed ratio is determinedutilizing the ring gear/sun gear tooth ratios of the planetary gear sets1020, 1030 and 1040. The numerical value of the fifth forward speedratio is determined utilizing the ring gear/sun gear tooth ratios of theplanetary gear sets 1030 and 1040.

[0166] While the best modes for carrying out the invention have beendescribed in detail, those familiar with the art to which this inventionrelates will recognize various alternative designs and embodiments forpracticing the invention within the scope of the appended claims.

What is claimed is:
 1. A family of transmissions wherein each familymember comprises: an input shaft; an output shaft; first, second andthird planetary gear sets each having first, second and third members;said input shaft being continuously interconnected with a member of thethird planetary gear set, said output shaft being continuouslyinterconnected with another member of the third planetary gear set; afirst interconnecting member continuously interconnecting said firstmember of said first planetary gear set with said first member of saidsecond planetary gear set; a second interconnecting member continuouslyinterconnecting said second member of said first planetary gear set andsaid second member of said second planetary gear set with a transmissionhousing; a first clutch selectively interconnecting said third member ofsaid first planetary gear set with said input shaft, said output shaft,or a member of said third planetary gear set; a second clutchselectively interconnecting said third member of said second planetarygear set with said input shaft, said output shaft, or a member of saidthird planetary gear set; a third clutch selectively interconnectingsaid first interconnecting member with said input shaft, said outputshaft, or a member of said third planetary gear set; a fourth clutchselectively interconnecting said third member of said first or secondplanetary gear set or said first interconnecting member with said inputshaft, said output shaft, or a member of said third planetary gear set;and said first, second, third or fourth clutches being engaged incombinations of two to establish at least five forward speed ratios anda reverse speed ratio between said input shaft and said output shaft. 2.The family of transmissions in claim 1, wherein planet carrier assemblymembers of each of said planetary gear sets are of the single-piniontype.
 3. The family of transmissions in claim 1, wherein a planetcarrier assembly member of at least one of said planetary gear sets isof the double-pinion type.
 4. A family of transmissions having aplurality of family members wherein each family member comprises: aninput shaft; an output shaft; a planetary gear arrangement having first,second and third planetary gear sets, each planetary gear set havingfirst, second and third members; said input shaft being continuouslyinterconnected with a member of the third planetary gear set, saidoutput shaft being continuously interconnected with another member ofthe third planetary gear set; a first interconnecting membercontinuously interconnecting said first member of said first planetarygear set with said first member of said second planetary gear set; asecond interconnecting member continuously interconnecting said secondmember of said first planetary gear set and said second member of saidsecond planetary gear set with a transmission housing; and fourselectively engageable clutches for selectively interconnecting saidmembers of said planetary gear sets with said input shaft, said outputshaft, said first interconnecting member, or another member of saidplanetary gear sets, said clutches being engaged in combinations of twoto establish at least five forward speed ratios and one reverse speedratio between said input shaft and said output shaft.
 5. The family oftransmissions defined in claim 4, wherein a first of said four clutchesis selectively operable for interconnecting said third member of saidfirst planetary gear set with said input shaft, said output shaft, or amember of said third planetary gear set.
 6. The family of transmissionsdefined in claim 4, wherein a second of said four clutches isselectively operable for interconnecting said third member of saidsecond planetary gear set with said input shaft, said output shaft, or amember of said third planetary gear set.
 7. The family of transmissionsdefined in claim 4, wherein a third of said four clutches is selectivelyoperable for interconnecting said first interconnecting member with saidinput shaft, said output shaft, or a member of said third planetary gearset.
 8. The family of transmissions defined in claim 4, wherein a fourthof said four clutches is selectively operable for interconnecting saidthird member of said first or second planetary gear set or said firstinterconnecting member with said input shaft, said output shaft, or amember of said third planetary gear set.
 9. The family of transmissionsin claim 4, wherein planet carrier assembly members of each of saidplanetary gear sets are of the single-pinion type.
 10. The family oftransmissions in claim 4, wherein a planet carrier assembly member of atleast one of said planetary gear sets is of the double-pinion type.